Trampoline having cushion mechanism

ABSTRACT

The trampoline contains a flexible jumping bed enclosed by a closed frame supported by a number of legs on the ground. A cushion element such as a spring, a rubber block, or a hydraulic or air buffering device is provided at each connection between the frame and the legs. The cushion element absorbs part of the downward force exerted on the frame and the legs so that an extended operation life of the trampoline is achieved.

(a) TECHNICAL FIELD OF THE INVENTION

The present invention generally relates to trampolines, and more particularly to a trampoline having cushion mechanism for enhancing its operation life.

(b) DESCRIPTION OF THE PRIOR ART

Trampoline is a common exercise device. As shown in FIGS. 1 and 2, a conventional trampoline contains a flexible jumping bed 20 enclosed by a circular frame 10 and the jumping bed 20 is stretched around its rim by a number of springs 25 to the frame 10.

A number of curved segments 11 and 13 are cascaded end-to-end alternately into the circular frame 10 by joining the ends 110 and 130 of neighboring segments 11 and 13 together. The trampoline further contains a number of legs 15, each formed by two vertical beams 16 and a bottom beam 17 into a U-like shape. Near the two ends of each segment 11, two downward sleeves 12 are provided so as to receive two vertical beams 16 from two legs 15, respectively, by joining their ends 120 and 160 together. As such, the frame 10, and therefore the jumping bed 20, is supported by the legs 15 above the ground for an appropriate height.

Conventionally, the design of the trampoline assumes that a user of an average weight jumps up and down in the center of the jumping bed 20. Then, based on the force exerted on the jumping bed 20, an appropriate number of springs 25 and the strength of each spring 25 are determined. As shown in FIG. 3, during the exercise, each spring 25 undergoes a diagonal force c1 with a horizontal component b1 and a vertical component a1. The horizontal component b1 is absorbed by the spring 25 while the vertical downward component a1 is completely borne by the frame 10 and the legs 15. The included angle between c1 and b1 represents the amount of distortion to the spring 25.

As the springs 25 undergo constant distortion after a period of usage, the flexibility of the springs 25 begins to decay. Since the user sometimes would land on the jumping bed 20 near the rim, this will deteriorate the springs 25 even faster. With less absorption by the springs 25, the greater vertical downward components a1, on one hand, further distort the springs 25 and, on the other hand, render stronger impact to the frame 10 and the legs 15. All these will contribute to the shortened operational life of the trampoline as the spring 25 or the frame 10 or the legs 15 are worn or broken down.

SUMMARY OF THE INVENTION

Accordingly, a novel trampoline is provided herein which is characterized by its extended operational life span.

In order to achieve the extended operation life, the trampoline adopts a cushion mechanism at the connections between the frame and the legs to absorb the vertically downward force of the user jumping on the trampoline. As such, the springs will suffer less distortion and therefore will not decay or wear down easily and shortly. In addition, the cushion mechanism lessens the direct impact exerted on the frame and the legs to prevent their broken down from overloading. Besides the extended operation life, the trampoline further enjoys the advantage of requiring a less number of springs and less rigid springs, which is readily translated into a smaller production cost.

The foregoing objectives and summary provide only a brief introduction to the present invention. To fully appreciate these and other objects of the present invention as well as the invention itself, all of which will become apparent to those skilled in the art, the following detailed description of the invention and the claims should be read in conjunction with the accompanying drawings. Throughout the specification and drawings identical reference numerals refer to identical or similar parts.

Many other advantages and features of the present invention will become manifest to those versed in the art upon making reference to the detailed description and the accompanying sheets of drawings in which a preferred structural embodiment incorporating the principles of the present invention is shown by way of illustrative example.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective diagram showing a conventional trampoline.

FIG. 2 is a schematic diagram showing a connection between the frame and the legs of the trampoline of FIG. 1.

FIG. 3 is a schematic diagram showing how a force is exerted on a spring of the trampoline of FIG. 1.

FIG. 4 is a schematic diagram showing the joining of the frame and the legs according to an embodiment of the present invention.

FIG. 5 is a perspective diagram showing a trampoline according to the present invention.

FIG. 6 is a schematic diagram showing a cushion mechanism adopted in FIG. 4.

FIG. 7 is a schematic diagram showing a cushion mechanism adopted in another embodiment of the present invention.

FIG. 8 is a schematic diagram showing how a force is exerted on a spring of the trampoline of FIG. 5.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The following descriptions are exemplary embodiments only, and are not intended to limit the scope, applicability or configuration of the invention in any way. Rather, the following description provides a convenient illustration for implementing exemplary embodiments of the invention. Various changes to the described embodiments may be made in the function and arrangement of the elements described without departing from the scope of the invention as set forth in the appended claims.

As shown in FIG. 5, a trampoline according to the present invention contains a flexible jumping bed 60 enclosed by a closed frame 50 (circular in this embodiment) and the jumping bed 60 is stretched around its rim by a number of springs 65 to the frame 50.

As shown in FIG. 4, a number of segments 51 and 53 are cascaded end-to-end alternately into the closed frame 50 by joining the ends 510 and 530 of neighboring segments 51 and 53 together. The trampoline further contains a number of legs 55, each formed by two vertical beams 56 on a bottom beam 57 into a U-like shape. Please note that the bottom beam 57 is curved slightly upward to enhance its strength and reliability. Near the two ends of each segment 51, two downward connectors 52 are provided so as to join two vertical beams 56 from two legs 55, respectively, by joining their ends 520 and 560 together. In other words, a leg 55 has an appropriate span so that its two vertical beams 56 are joined to two downward connectors 52 from two segments 51, respectively, with a segment 53 sandwiched therebetween, to prevent the two segments 51 from separation. As such, the frame 50, and therefore the jumping bed 60, is supported by the legs 55 above the ground for an appropriate height.

As shown in FIG. 6, the top end 560 of a vertical beam 56 is plugged into the bottom end 520 of a downward connector 52, which is a sleeve in the present embodiment. Inside the bottom end 520, a cushion element 58 is provided to interface with the top end 560 of the vertical beam 56. In the present embodiment, the cushion element 58 is a spring but it can also be a rubber block, or a hydraulic or air buffering device. As shown in HG 7 which is another embodiment of the present invention, the bottom end 520 of a downward connector 52 is plugged into the top end 560, which is a sleeve in the present embodiment, of a vertical beam 56. Inside the top end 560, a horizontal blocker 59 is provided to support a cushion element 58 (i.e., a spring in the present embodiment) for interfacing with the downward connector 52's bottom end 520.

The function of the cushion element 58 is illustrated in FIG. 8. As shown, when a user jumps on the jumping bed 60, each spring 65 undergoes a diagonal force c1 with a horizontal component b1 and a vertical component a3. The horizontal component b1 is again absorbed by the spring 65. On the other hand, a part of the downward component a3 is absorbed by the cushion element 58 and only a remaining component a2 is borne by the frame 50 and the legs 55. The included angle between the resulted diagonal force c2 and b1, representing the amount of distortion to the springs 65, therefore will be significantly smaller compared to that of a trampoline of prior art (as shown in FIG. 3). As the springs 65 undergo lesser distortion, the flexibility of the springs 65 decays in a much slower rate. Together with the weaker impact being afforded to the frame 50 and the legs 55, a lengthened operational life of the trampoline is achieved.

It will be understood that each of the elements described above, or two or more together may also find a useful application in other types of methods differing from the type described above.

While certain novel features of this invention have been shown and described and are pointed out in the annexed claim, it is not intended to be limited to the details above, since it will be understood that various omissions, modifications, substitutions and changes in the forms and details of the device illustrated and in its operation can be made by those skilled in the art without departing in any way from the spirit of the present invention. 

1. A trampoline, comprising a closed frame; a plurality of legs beneath and joining to said closed frame by a plurality of connections so as to support said closed frame above the ground for an appropriate height; a flexible jumping bed enclosed by said closed frame; a plurality of springs between the rim of said jumping bed and said closed frame to stretch said jumping bed; and a plurality of cushion elements provided at said connections, respectively.
 2. The trampoline according to claim 1, wherein said frame is formed by cascading end-to-end a plurality of first segments and a plurality of second segments alternately; each first segment comprises two downward connectors; and each leg comprises two vertical beams joining to two downward connectors from two first segments, respectively, with a second segment sandwiched between said first segments, to form two of said connections.
 3. The trampoline according to claim 2, wherein at least one downward connector is a sleeve; a vertical beam of a leg is plugged into said sleeve; and a cushion element is housed inside said sleeve to interface with said vertical beam.
 4. The trampoline according to claim 2, wherein the top end of at least one vertical beam is a sleeve, a downward connector of a first segment is plugged into said sleeve; a blocker is provided inside said sleeve; and a cushion element is housed inside said sleeve and supported by said blocker to interface with said downward connector.
 5. The trampoline according to claim 1, wherein said cushion element is one of a spring, a rubber block, a hydraulic buffering device, and an air buffering device. 